Yesterday, at SMX West during the mobile-first index panel, I asked Gary Illyes of Google what is the hold back on launching the mobile-first index.

Gary Illyes responded that Google is looking to see a “quality neutral” launch. That means that when they flip the switch to be a mobile-first index, they don’t want the search results to change much. They want the quality of the search results to pretty much be at the same level or a bit better. If they do not see a “quality neutral” data set, they will not launch.

Getting to “quality neutral” is not easy and it is tricky he said. They are looking at a whole new web, a mobile web, and it is a whole new index. So it is tricky.

Gary has said this before but always nice to hear him say it at a show.

Here are some tweets from the session on this point:

Forum discussion at Twitter.